ASHLEE Simpson and Evan Ross look quite the star couple, despite having jet lag and having been out late the night before we meet. Ross is clean-cut and handsome, clad in a tailored jacket with a polo-neck top, Simpson adding a touch of California dazzle to a grim UK day with her expensive check print suit, flawless make-up and bright blonde hair.
The US couple's working partnership comes after they married in 2014, and after welcoming daughter Jagger Snow in 2015. (They also have Simpson's son Bronx Mowgli from her first marriage to Fall Out Boy rocker Pete Wentz.)
It might seem like an unusual collaboration: Simpson, the sister of singer and actress Jessica Simpson, is a pop-rock singer at heart.
Actor Ross, the son of music icon Diana Ross, has starred in the Hunger Games films and teen series 90210 among other things, but he's also dabbled in a bit of R&B music previously.
They released their first music together last year as an EP alongside a reality TV series documenting their musical endeavours.
"We started working on music together, and were already documenting going to the studio. It was just the right time for us to make a show," Simpson explains.
It's a return to the small screen for 34-year-old Simpson who, along with her pop career, had her own reality series back in 2004 and 2005, a spin-off from her sister's pop culture favourite Newlyweds.
It also marks her musical comeback, years after the release of her third album Bittersweet World in 2008.
Although she initially "hesitated" at the idea, she says: "I thought it would be good if people can catch up and see where I am in my life."
Ross (30) chips in: "We weren't like, 'let's make a TV show'. We thought, 'it's kinda cool we're making music together, we should probably document it'. But we wanted to make something that was more like a docu-series. We didn't want a gossipy, dramatic reality show."
While the series, called Ashlee + Evan to match their moniker as a musical duo, is largely about the music, it's also about "family and love", and has cameos from relatives, including Diana. Jagger and Bronx are in the show a little bit, too.
"You see our lives and you see our friends, and our daughter and son are so cute," Simpson gushes.
"You get to see our inspirations, you see us in the studio, and you get to see Earth, Wind and Fire playing, laying down tracks," Ross adds, noting the legendary funk group's bassist Verdine White, who worked with them on the EP.
Simpson and Ross released one track from their EP along with each episode when the show aired in America, and they have a second half of the EP coming out later this year.
Their music, Ross says, has a "hip hop and soulful vibe" to it, which is at odds with what Simpson's earlier style.
"Because we do different genres, we were very clear that the music was going to be more about being love songs," Ross says.
"Songs that are just us, that fit both of our vibes, and what we listen to. It wasn't one particular sound," Simpson adds.
Given this amalgamation of their styles, and the fact they are husband and wife, are they at all worried about how their musical partnership is perceived?
Simpson shakes her head. "Evan grew up in this world with his mom, and I grew up in it too," she states. "We don't ever focus on that."
It's also worth noting that Simpson has already endured one of the most humiliating things a singer could ever face: being caught lip syncing during a seemingly live performance.
Simpson was caught out when the wrong backing track, complete with vocals, was played during her performance on US TV show Saturday Night Live in 2004. She then did a bizarre jig on stage, in an attempt to steal the moment back.
The cringeworthy incident made headlines across the world, and has followed her ever since. Nothing could bring her down now, though, she says.
"That moment definitely made me strong," she insists. "It was fight or flight, and I learned to fight, get up, and go on tour the next day. Moments like that, they make you strong, and I can look back and go, 'gosh, I am so proud of all the records that I made, and I'm so proud of all the tours that I did'.
She adds: "But I just wanna go and give that 19-year-old me a hug. It's so sad, I was so young."
The admittedly awkward moment didn't affect her career too much, though, and she went on to have a string of pop hits, including Pieces Of Me and Boyfriend, and her first two albums topped the charts in the US.
Following her extended hiatus to focus on motherhood, Simpson says she is delighted to have returned to music alongside Ross. She is also going to start finally working on a fourth solo record.
"I'm definitely going to have a more a pop-rock kind of thing for my album," she says. "But I feel like, now if I don't have Evan with me, I'm like – 'Where are you?' It's so much fun working with you!" she says, turning to face her husband.
"Because I'm like, half-assistant, half-husband," he quips.
"No, you're my best friend!" she fires back.
Ross chuckles. "We work well together, so it's fun, and I think it's going to be weird to work separately for a while.
"But it's nice to be able to create together for now. It's fun."
:: Ashlee + Evan airs on Sundays on E!. Ashlee and Evan's debut EP Ashlee + Evan is out now.
